Circular-knife grinder



(No Model.)

J. MALLON. GIRGULAR KNIFE GRINDER.

No. 468,535. Patented Feb. 9, 1892.

W mm) NITED STATES PATENT OFFICE.

w JAMES MALLON, OF NEIV ORLEANS, LOUISIANA.

CIRCULAR-KNIFE GRINDER.

SPECIFICATION forming part of Letters Fatent No. 468,535, dated February 9, 1892.

Application filed October 12, 1891. Serial No. $08,478. (No model.)

To aZZ whom it may concern:

Be it known that 1, JAMES MALLON, a citizen of the United States, residing at New Orleans, in the parish of Orleans and State of same.

I Myinvention has relation to improvements in machines for grinding circular knives; and it has for its general object to provide such a machine embodying a construction whereby the grinding-wheel may be adjustably fixed with respect to the bed of the machine and the knife to be ground, so that the latter may be beveled at various angles.

A further object of the invention is to back the spindle of the grinding-wheel by a spring, whereby the grinding-wheel will always be held in engagement with the knife regardless of irregularities in the face of said wheel.

Other objects and advantages will be fully understood from the following description and claims when taken in conjunction with the accompanying drawings, in which- Figure 1 is a perspective view of my improved machine, a circular knife being illustrated in a position to be ground; and Fig. 2 is a top plan view, partly in section of the same.

Referring by letter to said drawings, A indicates the bed of my improved machine, which is suitably mounted and is provided with a longitudinal slot a, for a purpose presently pointed out. Suitably fixed upon or formed integral with a raised portion 1), which is connected to or formed integral with-the bed A, are journal-bearings B, which are preferably arranged in an oblique line with respect to the bed. J ournaled in the bearings B is the spindle or shaft 0, upon which the knife to be ground is mounted, which spindle or shaft is preferably disposed obliquely with respect to the bed, as I find from experience ingwvheel. This shaft 0 is provided at one end with a crank-arm, as c, and has its opposite end threaded to receive anut, as cl, which serves to secure the knife upon the shaft. Inasmuch as knives of differentcharacters have central holes of various sizes, I have provided awasherB, of truncated-cone form, which is mounted on wthe shaft 0 and adjusted by the nut (1 into the opening of the knife to center the same. Fixed upon the shaft 0, adjacent to the threaded end thereof, is a cup-shaped flange D, the edge of which bears against the inner face of the knife and serves to hold the same securely in position. By the provision of this flange D it will be readily perceived that the shaft is adapted to receive and securely hold blades with hubs as well as hubless blades.

E indicates the adjustable block for supporting the spindle of the grinding-wheel. This block E, as better illustrated in Fig. 2 of the drawings, is provided with a longitudinal slot or slots e, through which take bolts f, which also take through the slot at in the bed and are adapted to receive nuts on the under side of the bed, (not shown,) whereby it will be seen that the block and the grinding-wheel carried thereby may be adjustably fixed at various angles, so that bevels of various angles may be formed upon the blade or knife to be ground.

Suitably connected to or formed integral with the upper side of the adjustable block E and disposed longitudinally with respect thereto are parallel guides h, which preferably have their inner lower edge beveled, so as to afford between them a guideway of dovetail form in cross-section to receive the base-plate of the adjustable carriage F, which is provided at or adjacent to its ends with angular branches 2', in which bears the tensionbar G, which impinges at one end against the inner end of the grinding-wheel spindle II and serves to regulate the pressure of said grinding-wheelagainsttheknifebeingground, as will presently appear. Surrounding the tension-bar G and bearing at one end against the inner side of the rear branch 6 and at its opposite end against a shoulder or lug on said bar is a coiled spring Lwhioh exerts a yielding pressure against the tension-bar and the spindle H, whereby it will be seen that the grinding-Wheel will be constantly held against the knife regardless of irregularities in the face of said wheel.

The grinding or emery wheel M, which is suitably mounted upon the outer end of the spindle H, may be of the ordinary or any approved construction.

The spindle H, as better illustrated in Fig. 2 of the drawings, is journaled in suitable bearings upon the adjustable block E in alignment with the tension-bar G, and a collar or lug is provided at its inner end to prevent its casual displacement.

Preferably formed integral with the baseplate of the adjustable carriage F is a stud or lug j, against which bears the adjusting-lever K, which is pivotally connected to the block E, and it is adapted to engage the teeth of a rack L, whereby the carriage and tensionbar may be adj ustably fixed.

Although I have specifically described the construction and relative arrangement of the several elements of my invention, yet I do not desire to be confinedto the same, as in practice such modification may be made as fairly falls Within the scope of my invention.

In operation, after the knife has been mounted on the crank-shaft and the grinding or emery wheel suitably adjusted the knife is rotated and by frictional contact rotates the grinding-wheel. in an opposite direction,

whereby it will be seen that a new surface is always presented to the knife.

Having described my invention, what I claim, and desire to secure by Letters Patent,

l. Ina machine forgrindingcircular knives, the combination, with the longitudinally-adjustable shaft carrying a grinding-wheel, of a spring backing said shaft, an adjustable carriage bearing against the spring, a lever adapted to engage and adjust the carriage to regulate the pressure of the spring, and a suitable means for adj ustably fixing said lever, substantially as and for the purpose set forth.

2. Inamachine fol-grinding circular knives, the combination, with the longitudinally-adjustable shaft carrying a grinding-wheel, of an adjustable carriage, a tension-bar bearing in said carriage and adapted to abut against the inner end of the adj ustable shaft, a spring interposed between a shoulder on the tensionbar and the rear branch of the adjustable carriage, and a suitable means for adj ustably fixing the carriage to regulate the tension of the pressure-spring, substantially as and for the purpose set forth.

In testimony whereof I affiX my signature in v presence of two witnesses.

JAMES MALLON. Witnesses:

WILLIAM WILSON, PERCY D. PARKS. 

